Condition Analysis
AI-powered assessment using site data and 14-day weather history
The rock at Cow and Calf is almost certainly still wet internally following a prolonged period of frequent rain. There has been significant precipitation over the last two weeks with no sustained dry spell, and today itself has 1mm forecast — conditions are not suitable for climbing on gritstone.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and lower walls tend to hold seepage at their bases after prolonged wet periods, and the recent 72.4mm over 28 days means deep saturation is likely despite the exposed aspect.
- The S/SW aspect and exposed position are helpful for drying, but the lack of any consecutive dry period longer than 3 days since late March means the rock has never had a chance to dry out fully.
- At 260m altitude, overnight temperatures have been dropping to 1–2°C, slowing overnight drying and meaning the rock enters each morning still holding significant moisture from the previous day.
- The open moorland setting means the ground around the crag will be waterlogged from the cumulative 72mm in 28 days — if the peat and grass are sodden, the rock is almost certainly still damp internally.
Warnings
3
- Climbing on wet gritstone causes irreversible hold breakage and route degradation — Yorkshire gritstone ethics are clear that damp rock must not be climbed.
- The prolonged wet period means even apparently dry surfaces may be hiding significant internal moisture — do not trust surface appearance alone.
- Freeze-thaw risk remains possible with overnight lows near 0°C and saturated rock at 260m altitude.
Reasoning
With 10.1mm on April 11, 2.8mm on April 12, and 1mm today, plus a background of 72.4mm in 28 days with no sustained dry spell, the gritstone is almost certainly saturated well beyond the critical 1% threshold internally.
Despite the S/SW aspect and reasonable wind exposure, there has been no period of 48+ consecutive dry hours in the last week; the rock has been repeatedly re-wetted before any meaningful drying could occur.
At this level of cumulative saturation, gritstone compressive strength is likely reduced by 30%+ and holds are at significant risk of breakage, particularly on well-trafficked problems on the Calf boulder.
Early spring conditions with cool temperatures (average 7.9°C over 7 days) and overnight lows near freezing mean drying is slow, and there is still residual freeze-thaw risk that compounds the wet-rock damage concern.
Contributing Factors
7
10.1mm fell on April 11 followed by 2.8mm on April 12 and 1mm today, with no meaningful dry window since.
72.4mm over the last 28 days with repeated re-wetting events means deep pore saturation is very likely in this porous gritstone.
Zero consecutive dry days as of today — the rock has had no opportunity for the 48–72 hours of dry weather needed after heavy rain.
The S/SW aspect and exposed hilltop position give Cow and Calf above-average drying potential when dry weather does arrive.
Average temperature of 7.9°C over the past week and overnight lows of 1–4°C significantly slow evaporation rates.
Average humidity of 74% over the last week limits evaporative drying, though not catastrophically high.
3.8mm forecast for April 14 and 3.0mm for April 15 means the rock will be re-wetted again before any drying can take hold.
Recommendations
3
- Do not climb today — the gritstone is almost certainly wet internally despite any surface drying, and climbing risks permanent hold damage.
- Wait for at least 48 hours of genuinely dry weather with temperatures above 10°C before considering a visit; the earliest realistic window may be April 17–18 if the forecast holds.
- Check the ground condition at the base of the crag on arrival — if the peat and grass are sodden, the rock is not ready regardless of how the surface looks.
Previous Analyses
Do Not Climb
85%
2 days ago
The rock at Cow and Calf is almost certainly still wet internally following 10.1mm of heavy rain on April 11th and further light rain today (1.9mm), with no meaningful dry period since. The past month has been persistently wet (74.6mm in 28 days) with frequent light-to-moderate rain events preventing the gritstone from ever fully drying out, making climbing today irresponsible.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and surrounding blocks are fully exposed to weather from the south-west, which means the recent SW/W rain will have driven moisture directly onto the main climbing faces.
- The open moorland setting means the ground around the base of the boulders will be saturated from the wet month — a useful field indicator that the rock is still wet internally.
- Despite the S/SW aspect normally aiding drying, the lack of any consecutive dry days and persistent humidity above 70% have prevented meaningful evaporation from the porous gritstone.
- At 260m altitude in early April, overnight temperatures dropping near or below freezing (0.5°C forecast tonight) combined with saturated rock create a freeze-thaw damage risk.
Warnings
3
- Climbing on saturated gritstone causes irreversible hold breakage and route degradation — the BMC and Yorkshire climbing community strongly advise against it.
- Freeze-thaw cycling risk is active with overnight lows near 0°C on saturated rock at 260m altitude.
- The rock surface may appear dry in sunny spells while remaining dangerously weakened internally — do not be fooled by surface appearances.
Reasoning
With 10.1mm falling yesterday and 1.9mm today on top of a relentlessly wet month (74.6mm in 28 days with almost no consecutive dry days), the gritstone will be deeply saturated — well above the critical 1% saturation threshold where significant weakening begins.
There has been zero consecutive dry days; although the exposed S/SW aspect and moderate winds would normally aid drying, the constant replenishment of moisture from frequent rain events means no meaningful drying has occurred.
At estimated saturation levels well above 60%, the gritstone faces compressive strength reductions of 10–50%, with serious risk of hold breakage and grain loosening — climbing now would cause permanent damage to routes.
Early April in Yorkshire at 260m brings overnight near-freezing temperatures (forecast lows of 0.5–0.8°C), and with saturated rock this creates active freeze-thaw cycling risk that compounds structural vulnerability.
Contributing Factors
7
10.1mm fell yesterday and 1.9mm today, with no dry period in between — the rock has had no opportunity to begin drying.
74.6mm over 28 days with almost no consecutive dry days means the gritstone has been chronically saturated with no chance to dry internally.
There have been no consecutive dry days recently, which is far short of the minimum 48–72 hours needed after heavy rain on porous rock.
The south/south-west facing exposed position would normally promote fast drying, but this advantage is negated by the continuous rainfall.
Today's 28 km/h SW wind aids surface evaporation, but cannot compensate for rain falling on the same day.
Forecast overnight lows near 0°C on saturated rock create active freeze-thaw risk at this altitude, threatening cumulative structural damage.
Humidity in the low-to-mid 70s is moderate but combined with cool temperatures limits evaporative drying potential.
Recommendations
3
- Do not climb today — the gritstone is almost certainly saturated internally and climbing risks permanent hold damage.
- Wait for a minimum of 48–72 hours of completely dry weather before considering a visit; given the prolonged wet period, longer may be needed.
- Check the ground at the base of the boulders before climbing — if the moorland soil is damp, the rock is certainly still wet inside.
Do Not Climb
90%
3 days ago
Ilkley Cow and Calf is currently wet from today's 4.2mm rainfall with no preceding dry period — the rock will be saturated and structurally compromised. The past two weeks have seen frequent rain (67.9mm in 28 days) with only brief dry spells, meaning the gritstone has had no opportunity to dry out fully at depth.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and surrounding blocks have varied aspects, but even the south-facing surfaces will be wet given today's rain and no drying time.
- The open moorland setting at Cow and Calf means the exposed wind will aid future drying, but the saturated moorland ground and drainage from above will keep the base of boulders and lower crag sections damp for longer.
- The popular lowball problems on the Calf boulder are particularly vulnerable — they sit close to the moor surface where moisture lingers and where repeated traffic on weakened holds causes the most damage.
- After the prolonged wet spell from late March through early April, deep moisture within the gritstone will persist well beyond surface drying; even during the brief dry window (Apr 6–8) the rock likely did not fully dry internally before rain returned.
Warnings
3
- Climbing on wet gritstone causes permanent, irreversible damage to holds — Cow and Calf is a heavily used venue where this damage accumulates rapidly.
- Freeze-thaw conditions are forecast for April 14 with saturated rock — avoid climbing on or immediately after this date as structural integrity is further reduced.
- The surface may appear dry before the interior has recovered; after this prolonged wet period, do not trust surface appearance alone — check ground moisture at the crag base.
Reasoning
The rock is currently wet from today's 4.2mm of rain, following 0.6mm yesterday and 1.8mm on April 9th, with no meaningful consecutive dry days — the gritstone is saturated both at surface and internally.
Despite the south/south-west aspect and exposed wind position, there has been zero drying time since today's rain, and the cumulative effect of nearly 68mm over the past month means the rock retains deep moisture even during brief dry intervals.
With the gritstone saturated from repeated wetting events, compressive strength is significantly reduced (potentially 30%+ loss), and climbing would risk hold breakage and accelerated erosion on this heavily trafficked venue.
Early spring conditions with cool temperatures (averaging 7.7°C over the past week) and persistent dampness mean drying is slow; overnight frost risk (min -0.7°C on Mar 26, forecast -1.3°C on Apr 14) adds freeze-thaw concern for saturated rock.
Contributing Factors
7
4.2mm of rain fell today with zero consecutive dry days, meaning the rock surface and interior are actively wet.
67.9mm over the past 28 days with only a brief 3-day dry window (Apr 6–8) means the gritstone has been repeatedly re-saturated and holds deep internal moisture.
Temperatures averaging 7.7°C over the past week are adequate but not ideal for rapid drying — not cold enough to prevent evaporation entirely but far from summer conditions.
The crag's exposed moorland position with 25+ km/h winds today and in the forecast will significantly aid drying once rain stops, but this benefit cannot act on currently wet rock.
The favourable aspect maximises solar radiation for drying, but with overcast rainy conditions today this advantage is not being realised.
Forecast lows of -1.3°C on April 14th following recent rain mean saturated rock faces freeze-thaw damage risk, further weakening the gritstone.
The forecast shows further rain on April 12 (2.6mm), April 13 (1.8mm), April 14 (0.7mm), and a heavy event on April 15 (10.4mm), preventing any sustained drying window for days.
Recommendations
3
- Do not climb today — the rock is actively wet and structurally compromised; respect Yorkshire gritstone ethics and wait for a sustained dry spell.
- Monitor conditions from April 16 onwards when the forecast shows the first potential dry window with good wind; check the base of the crag for dry ground as a reliable field indicator.
- If visiting Ilkley this week, consider the nearby Chevin limestone or an indoor wall rather than risking damage to these irreplaceable gritstone routes.
Do Not Climb
70%
4 days ago
The Cow and Calf has had a persistently wet spring with 70.8mm over the last 28 days and no sustained dry spell; yesterday's 1.8mm rain followed by today's 0.5mm means the rock has had zero consecutive dry days. Despite a brief warm dry window (6–8 April), the repeated light rain events and high cumulative moisture loading mean the gritstone is very likely still damp internally, and we recommend not climbing today.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and main crag faces S/SW and benefit from good solar exposure, but the repeated rain events throughout late March and early April have prevented a meaningful drying cycle from completing.
- The exposed moorland position provides excellent wind drying — strong westerlies (30–42 km/h) have been frequent — but high humidity (often 80%+) has limited their drying effectiveness.
- Lower sections of the Calf boulder and routes near the base will retain moisture longest due to downward drainage; the brief 3-day dry spell (6–8 April) was insufficient to dry deeply saturated gritstone after 70mm of cumulative rain.
- Ilkley Moor's peaty ground holds water extensively; if the ground at the base of the crag is visibly damp, the rock is almost certainly still wet internally.
Warnings
2
- Climbing on wet or internally damp gritstone causes permanent, irreversible damage to holds and route surfaces — Yorkshire gritstone ethics strictly prohibit this.
- Freeze-thaw conditions are forecast for April 13 (min -0.3°C) following rain, which can weaken already-saturated rock and increase hold breakage risk.
Reasoning
With 70.8mm of rain in 28 days and only a 3-day dry window before rain returned on April 9th, the gritstone is likely saturated internally despite any surface drying from the warm spell on 6–8 April.
The S/SW aspect and exposed position are favourable, but the brief dry window of 6–8 April (with temps reaching 19.5°C) was interrupted by 1.8mm on April 9th and 0.5mm today, resetting surface drying and preventing deep moisture from escaping.
Prolonged saturation over the past month combined with overnight temperatures near or below freezing (min -0.7°C on March 26, and forecast -0.3°C on April 13) creates a real freeze-thaw risk and elevated hold breakage potential on this porous gritstone.
Early spring conditions in Yorkshire remain marginal — short days, cool average temperatures (~8°C), and frequent Atlantic frontal systems keep the rock in a near-constant cycle of wetting without adequate drying intervals.
Contributing Factors
6
Rain fell yesterday (1.8mm) and today (0.5mm), meaning there has been no uninterrupted drying period since the last significant rainfall.
70.8mm over 28 days represents persistent saturation loading with no extended dry spell to allow deep drying of the porous gritstone.
The S/SW aspect and exposed moorland position maximise solar gain and wind drying when conditions allow, making this one of the faster-drying gritstone venues.
The promising 3-day dry window (6–8 April, up to 19.5°C) was cut short by rain on April 9th and today, preventing completion of deep drying after weeks of accumulated moisture.
27.4 km/h SW wind with 64% humidity today provides reasonable surface drying potential, though insufficient alone after such recent rain.
Forecast minimum of -0.3°C on April 13 following rain on April 11–13 creates a freeze-thaw risk on potentially saturated gritstone.
Recommendations
3
- Do not climb today — the gritstone has had zero dry days and is very likely still damp internally despite any surface drying.
- If visiting, check the ground at the base of the Calf boulder: if the peat and soil are visibly wet, the rock will certainly be too damp to climb safely.
- The next realistic window may not arrive until after April 14 if the forecast holds, but even then will require at least 48 hours of genuinely dry weather to begin recovering from this prolonged wet period.
Marginal — Assess Conditions
60%
5 days ago
Three consecutive dry days (April 6–8) with warm temperatures up to 19.5°C and the S/SW aspect have provided reasonable drying, but the preceding weeks have been persistently wet (82.7mm in 28 days) with frequent light rain, meaning the rock may still hold internal moisture. Today's trace precipitation (0.3mm) is negligible, but conditions warrant on-site assessment before committing to climb.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Cow and Calf sits on open moorland with excellent wind exposure, and the S/SW aspect means the main faces received strong solar heating during the warm spell on April 7–8 (up to 19.5°C), significantly aiding surface drying.
- The base of the Calf boulder and any north-facing subsidiary walls will have dried much more slowly — check for damp patches at ground level and on shaded faces before climbing.
- The persistent wet March (82.7mm over 28 days) means the gritstone has been repeatedly saturated; even after three warm dry days, internal moisture may linger in thicker sections and lower portions of the rock.
- Ilkley Moor's peaty ground retains moisture and can wick dampness upward — if the peat/soil at the base of the boulders is still visibly moist, treat the rock as still drying internally.
Warnings
2
- The rock may appear surface-dry while retaining significant internal moisture from the very wet preceding weeks — do not assume dry surfaces mean safe conditions.
- Freeze-thaw cycles in late March combined with saturated rock may have weakened some holds; be vigilant for loose or crumbling features.
Reasoning
After three fully dry days (Apr 6–8) following 2.1mm on Apr 5, surface rock on south-facing aspects is likely dry, but 82.7mm of rain over the preceding 28 days means the gritstone has been deeply and repeatedly wetted, raising the risk of residual internal moisture.
The warm spell of April 7–8 (up to 19.5°C) with low humidity (53–67%) and the S/SW aspect provided excellent drying conditions, though wind was light on those days (13–22 km/h); the exposed position partially compensates, but three days is marginal after such a prolonged wet period.
Given the extended wet March with multiple wetting cycles and some overnight temperatures near or below freezing (e.g. -0.7°C on Mar 26, 1.2°C on Apr 6), cumulative freeze-thaw and saturation weakening may have compromised some holds, so climbers should test holds carefully.
Early April in Yorkshire is transitional — conditions are improving but the prolonged wet winter/spring means the rock has had limited opportunity to fully dry out, and overnight humidity remains high (80–89%), slowing the drying process overnight.
Contributing Factors
7
April 6–8 were fully dry with warm temperatures peaking at 19.5°C on April 8, providing solid evaporation conditions for surface and near-surface moisture.
82.7mm of rain over 28 days with frequent wetting events means the gritstone has been deeply saturated multiple times, and internal moisture takes much longer to dissipate than surface water.
The south/south-west facing aspect receives excellent spring solar radiation, which significantly accelerates drying on the main climbing faces.
The open moorland setting provides good wind exposure which aids evaporation, though winds were relatively light on the warmest drying days (Apr 7–8).
Overnight humidity has been consistently high (80–89%) which stalls drying during nighttime hours and can cause condensation on cooler rock surfaces.
0.3mm forecast today is negligible and unlikely to meaningfully re-wet the rock, but it does technically break the dry spell.
Recent overnight lows near or below freezing (e.g. -0.7°C on Mar 26, 1.2°C on Apr 6) combined with saturated rock raise concerns about cumulative freeze-thaw weakening of holds.
Recommendations
3
- Visually inspect the rock before climbing — check for dark patches, damp seepage lines, and moisture at the base of the Calf boulder; if the ground at the base is still moist, the rock likely retains internal moisture.
- Prioritise south-facing and overhanging problems on the main Calf boulder which will have dried fastest; avoid north-facing walls, low-level slabs, and any areas with visible dampness.
- Test holds carefully by tapping before committing weight, as the prolonged wet period and freeze-thaw cycles may have weakened some features.
Marginal — Assess Conditions
55%
8 days ago
The last significant rain was 2.1mm on April 5th (yesterday), with repeated light showers throughout the preceding week totalling 8.1mm over 7 days, on top of a very wet month (83.8mm over 28 days). Today is dry with favourable winds and lower humidity (69%), and the S/SW aspect and exposed position help, but only one full dry day has elapsed since the last rain, which is insufficient to guarantee the rock is dry internally given the sustained wet background.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Cow and Calf's exposed moorland position and S/SW aspect mean it benefits from excellent wind drying and direct solar radiation, making it one of the faster-drying gritstone venues in Yorkshire.
- The base of the Calf boulder and lower north-facing sections can retain moisture significantly longer than the upper south-facing faces — check these areas carefully as seepage can persist.
- The surrounding moorland acts as a moisture reservoir; if the peat and grass at the crag base are still damp, the rock is very likely still holding internal moisture.
- March was exceptionally wet (83.8mm over 28 days) meaning the gritstone has been repeatedly saturated without adequate drying windows — cumulative moisture loading is a real concern.
Warnings
2
- The gritstone has been subjected to nearly 84mm of rain over the past month with very few drying windows — surface-dry rock may still be dangerously weakened internally.
- Climbing on damp gritstone causes permanent, irreversible damage to holds and routes; if in any doubt, please wait.
Reasoning
The rock received 2.1mm of rain yesterday and has had repeated wetting events throughout the past week (8.1mm in 7 days) on top of a very wet month (83.8mm in 28 days), meaning the gritstone is likely carrying significant internal moisture despite only needing to dry from yesterday's light shower on the surface.
The S/SW aspect and exposed position with moderate south winds (16.9 km/h) and low humidity (69%) today provide good drying conditions, but with only ~18 hours of effective drying since yesterday's last rain and the cumulative moisture loading from weeks of wet weather, full internal drying is unlikely.
Given the prolonged wet period and only one dry day, there is a meaningful risk that the gritstone retains enough internal moisture for holds to be weakened — particularly on lower sections and less-exposed faces.
Early April in Yorkshire at 260m means temperatures are still cool (overnight low 0.6°C today) and days are lengthening but not yet providing strong sustained solar drying; the overnight near-frost may have slowed evaporation during the night.
Contributing Factors
6
2.1mm fell on April 5th with the last trace at 17:00, giving only roughly 18-20 hours of drying time which is below the minimum 24-48 hour guideline for light rain on gritstone.
83.8mm over 28 days with very few consecutive dry days means the gritstone has been repeatedly saturated without adequate drying windows, likely leaving significant internal moisture.
The S/SW aspect and exposed moorland position provide excellent solar radiation and wind drying, making Cow and Calf one of the faster-drying gritstone crags in the region.
Today is forecast dry with 12.6°C max, 69% humidity, and moderate southerly winds at 16.9 km/h — good conditions for evaporation from the rock surface.
The overnight low of 0.6°C near freezing would have significantly slowed evaporation during the night hours, reducing total effective drying time.
The consistently wet weather pattern through March into early April means the rock may hold deep internal moisture that surface drying conditions alone cannot address in a single day.
Recommendations
3
- If visiting today, carefully check the base of the Calf boulder and surrounding ground — if the peat and grass are damp, do not climb on the gritstone as it will still be wet internally.
- Prioritise upper, south-facing, and overhanging faces which will have dried fastest; avoid lower sections, slabs, and any north-facing rock.
- Tomorrow (April 7th) looks significantly more promising with warm temperatures (16.7°C) and continued dry weather — waiting one more day would substantially increase confidence in dry conditions.
Do Not Climb
70%
9 days ago
Despite today's strong winds and lower humidity, the gritstone at Cow and Calf has had no meaningful dry spell — 83mm over the past 28 days with frequent topping-up showers, including 1.3mm today. The rock is almost certainly still holding significant internal moisture and should not be climbed on until a proper drying window has passed.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and surrounding blocks are relatively compact and exposed to wind on all sides, which aids surface drying, but the sheer volume of recent rainfall means internal saturation will persist despite the exposed position.
- The S/SW aspect is favourable for solar drying, but spring sun angles at this latitude and 260m altitude provide limited thermal input — especially with max temperatures only reaching ~8°C today.
- The open moorland setting means the ground around the base of the rocks acts as a useful moisture indicator: if the peat and grass are still damp (very likely given recent rain), the gritstone will be holding moisture internally.
- Cow and Calf's popularity means any damage from wet climbing is magnified across heavily trafficked holds — the Yorkshire gritstone ethic is unambiguous about not climbing on damp rock.
Warnings
2
- Do not be deceived by a dry-looking surface — with this much recent rainfall, the gritstone interior is almost certainly still saturated, risking hold breakage and permanent route damage.
- Overnight temperatures near 0°C combined with saturated rock create freeze-thaw conditions that further weaken the gritstone — climbing on freshly thawed rock is particularly dangerous.
Reasoning
With 83mm in the past 28 days, frequent showers through late March and early April (including 1.3mm today), and zero consecutive dry days, the gritstone is almost certainly saturated well beyond the critical 1% threshold at which significant strength loss begins.
Today's strong westerly wind (42.5 km/h) and lower humidity (68%) will help surface evaporation, but with rain falling today and no preceding dry spell, internal drying has barely begun — the S/SW aspect helps but cannot compensate for the persistent wetting cycle.
The repeated wet-dry cycling over the past month, combined with overnight temperatures dipping near or below freezing (0.8°C min today, -0.7°C on March 26), creates a significant freeze-thaw risk that compounds the already elevated hold-breakage danger from saturated gritstone.
Early April in Yorkshire is a transitional period with improving but unreliable conditions; the recent pattern of frequent frontal rainfall is typical for spring and means the rock has had no extended opportunity to dry out since winter.
Contributing Factors
7
83mm over 28 days with no dry spell longer than a few days, and rain falling as recently as today (1.3mm), means the gritstone has been repeatedly re-saturated.
There has been no meaningful drying window — the rock needs at least 48-72 hours of dry weather after this level of cumulative wetting, and it has had none.
Today's 42.5 km/h westerly wind on this exposed moorland site significantly aids surface evaporation, though it cannot dry the interior quickly.
The south/south-west facing rock receives good solar radiation when the sun is out, accelerating surface drying relative to north-facing crags.
At 68%, today's humidity is the lowest in over a week, allowing some net evaporation from the rock surface.
With a minimum of 0.8°C tonight and rock likely above 60% pore saturation, there is a real freeze-thaw damage risk if temperatures dip below zero at altitude.
The prolonged wet pattern through March means the rock has been in a near-continuously damp state for weeks, requiring an extended dry period to properly dry out.
Recommendations
3
- Wait for the promising dry spell forecast from April 6–8 (three consecutive dry days with warming temperatures and moderate winds) before climbing — conditions could become suitable by April 7 or 8 if the forecast holds.
- On arrival, check the ground at the base of the boulders: if the peat and soil are still damp, the gritstone will be holding internal moisture regardless of surface appearance.
- If you do visit during the dry window, start with the most exposed upper sections of the Calf boulder which will have dried fastest, and avoid any routes with visible seepage or darkened patches.
Do Not Climb
70%
10 days ago
The rock at Cow and Calf is almost certainly still damp internally despite strong winds today. The past two weeks have seen repeated rainfall events with no consecutive dry period longer than about a day, and today itself has received 2.1mm — the gritstone has had no meaningful opportunity to dry out.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and lower walls tend to retain seepage at their bases after prolonged wet spells, and the recent 81.7mm over 28 days means ground moisture levels will be high around the crag foot.
- The south/south-west aspect and exposed position are strong positives for drying, but these advantages are negated by the almost continuous cycle of rainfall events over the past fortnight with no extended dry window.
- At 260m on open moorland, overnight temperatures have been dropping near or below freezing (e.g. -0.7°C on March 26, 0.3°C on March 22), creating freeze-thaw risk on any internally saturated gritstone.
- The popular lower-tier problems and cracks on the main buttress are most vulnerable to retained moisture — even if upper faces feel dry, lower sections and horizontal breaks will hold water longer.
Warnings
2
- Climbing on wet gritstone causes permanent, irreversible damage to holds and routes — Yorkshire gritstone ethics are clear that damp rock should not be climbed on.
- Freeze-thaw risk is elevated given saturated rock and forecast overnight lows near 0°C on April 6; internally wet holds are at heightened risk of breakage.
Reasoning
With 14.4mm in the last 7 days spread across multiple events and 2.1mm falling today, the gritstone is almost certainly saturated internally — there has been no consecutive dry period long enough to allow meaningful drying.
The strong SW winds (42.5 km/h today) and south-facing aspect would normally accelerate drying considerably, but drying has been repeatedly interrupted by fresh rainfall every 1–2 days, preventing the rock from progressing beyond surface drying.
With repeated wetting cycles and overnight temperatures near freezing, there is a genuine risk of freeze-thaw damage to saturated gritstone, and climbing on internally wet rock risks hold breakage and permanent erosion.
Early April in Yorkshire is a transitional period where the accumulated winter moisture is only beginning to dissipate; the 81.7mm over 28 days reflects a typically wet spring pattern that keeps gritstone in poor condition.
Contributing Factors
8
14.4mm over the past 7 days with rain on 6 of the last 7 days means the rock has been repeatedly re-wetted with no sustained drying window.
2.1mm of precipitation today means the rock surface is actively wet and internal moisture is being topped up.
With zero consecutive dry days recorded, the gritstone has had no opportunity for the 48–72+ hours of dry weather needed after heavy cumulative rainfall.
Sustained SW winds of 42.5 km/h today on this exposed moorland site significantly accelerate surface evaporation when rain stops.
The south/south-west aspect maximises solar radiation exposure, which will help once a dry spell establishes.
81.7mm over 28 days represents a substantial cumulative wetting that saturates gritstone deeply, requiring an extended dry period to clear.
Average temperatures of ~7.4°C over the past week are marginal for efficient evaporative drying — not cold enough to halt drying but not warm enough to accelerate it meaningfully.
Overnight minima near or below freezing (0.4°C forecast April 6) on saturated gritstone create cumulative freeze-thaw damage risk during this spring transition.
Recommendations
3
- Do not climb today — the rock is actively wet and internally saturated from repeated recent rainfall.
- Monitor the forecast dry window from April 6–8; if it holds, conditions may become climbable by April 7 or 8 after 48+ hours of dry weather with warming temperatures.
- On arrival after the dry spell, check the base of the Calf boulder and lower walls — if the ground is damp or rock feels cool to the touch, the gritstone is still too wet internally.
Do Not Climb
70%
11 days ago
The rock at Cow and Calf is almost certainly still damp internally despite strong winds. The last 28 days have seen 81.7mm of rain with frequent wet spells, and today itself has 2.4mm of precipitation — there have been zero consecutive dry days, making adequate drying impossible.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Calf boulder and surrounding blocks have horizontal breaks and cracks that trap water and seep for days after heavy rain, particularly on the lower sections and around the base.
- The open moorland setting means the ground around the crag acts as a reliable moisture indicator — if the peat and grass at the base are wet, the gritstone is certainly still holding water internally.
- Despite the exposed S/SW aspect being favourable for drying, the persistent wet March (81.7mm in 28 days) means the gritstone has been repeatedly re-saturated before it could fully dry, accumulating internal moisture.
- The crag's popularity means any climbing on damp grit causes disproportionate cumulative damage — high traffic on weakened holds accelerates erosion at this heavily-used venue.
Warnings
3
- Do not climb today — the rock has had zero consecutive dry days and rain fell today; gritstone will be structurally weakened.
- Freeze-thaw risk is present over the next few nights with overnight lows near 0°C and saturated rock — hold breakage risk is elevated.
- The prolonged wet March means even surfaces that appear dry may be dangerously weakened internally; surface-dry does not mean safe.
Reasoning
With 2.4mm of rain today, 1.4mm yesterday, and repeated soakings over the past month totalling 81.7mm, the gritstone is almost certainly saturated internally despite any surface drying between showers.
Strong SW winds (38 km/h today) and the south-facing aspect help surface evaporation, but with zero consecutive dry days and repeated re-wetting, the rock has had no meaningful opportunity to dry through its full depth.
Gritstone that has been repeatedly saturated over weeks is at significant risk of hold breakage and grain loosening — the 10–50% compressive strength reduction applies, and the repeated wet-dry cycling compounds the damage.
Early spring conditions with overnight lows near or below freezing (0.4°C forecast tomorrow night, -0.4°C on April 6) combined with internal moisture create a real freeze-thaw risk that further weakens the rock.
Contributing Factors
7
2.4mm today with 1.4mm yesterday and 5.5mm on March 29 means zero consecutive dry days and ongoing surface wetting.
81.7mm over 28 days with no extended dry spell means the gritstone has been repeatedly re-saturated and likely holds significant internal moisture.
Sustained winds of 30–42 km/h over recent days significantly accelerate surface evaporation at this exposed moorland crag.
The favourable aspect provides above-average solar drying, especially as spring day length increases.
Overnight lows near or below 0°C forecast on April 4 and April 6 combined with internal moisture create freeze-thaw damage potential.
Average humidity of 79% over the last 7 days and 85% today limits the rate of evaporative drying.
Average temperature of 6.8°C over the last week is cool but not critically cold — drying occurs but slowly.
Recommendations
3
- Wait for at least 48 hours of fully dry weather before visiting — the earliest realistic window begins around April 6–7 if no further rain falls.
- Check the peat and soil at the base of the crag before climbing; if the ground is damp, the gritstone will be holding moisture internally.
- If you do visit, inspect hold surfaces carefully for any darkened patches or chalked areas that feel cool to the touch, which indicate sub-surface moisture.
Marginal — Assess Conditions
55%
12 days ago
The last significant rain was on March 30 (2.9mm), with only trace amounts on March 31 and April 1, giving roughly 2 days of mostly dry weather. However, the preceding weeks have been very wet (78.3mm in 28 days) and average temperatures remain cool, meaning deep moisture levels in the gritstone are likely still elevated. The S/SW aspect and exposed position help, but conditions need on-site verification.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The Cow and Calf's exposed moorland position and S/SW aspect mean it benefits significantly from the westerly winds that have dominated recently, giving it better drying potential than sheltered or north-facing gritstone venues.
- The Calf boulder and other large blocks can retain seepage at their base and in horizontal breaks — check lower sections and crack lines carefully as these hold moisture longest after prolonged wet periods.
- 78.3mm of rain over the past 28 days represents a very wet March; gritstone at 260m altitude in these conditions accumulates deep internal moisture that surface drying alone cannot resolve quickly.
- The moorland setting means the ground around the base of problems is a reliable moisture indicator — if peat and grass are sodden, assume the rock retains significant internal moisture.
Warnings
2
- The rock may appear surface-dry while still being significantly weakened internally after 78mm of rain in the past month — do not rely on surface appearance alone.
- Rain is forecast from April 3-5 which will re-saturate the rock; today may be the only marginal window before conditions deteriorate again.
Reasoning
With 78.3mm over 28 days and rain as recently as March 30 (2.9mm) plus traces on March 31 and April 1, internal moisture levels in the gritstone are likely still elevated despite surface drying.
Approximately 2 days of near-dry weather with moderate westerly winds (15-30 km/h) and the favourable S/SW aspect have aided surface drying, but cool temperatures (~7-10°C) and humidity averaging 79% limit evaporation rates significantly.
The prolonged wet period means internal pore saturation could still be above the threshold where significant strength loss occurs, posing a risk of grain loosening and hold breakage on stressed features.
Early April in Yorkshire at 260m brings cool overnight temperatures (near or below freezing on some nights recently) and variable conditions — the winter moisture legacy is still a factor at this time of year.
Contributing Factors
7
78.3mm over 28 days with frequent rain events means the gritstone has had very little chance to dry out at depth, maintaining elevated internal moisture.
Since March 30's 2.9mm, only trace precipitation has fallen (0.3mm combined), providing roughly 48 hours of near-dry conditions for surface drying.
The south/south-westerly facing rock receives good solar radiation during spring days, accelerating surface evaporation compared to north-facing crags.
Strong westerly winds (20-42 km/h) over recent days significantly aid evaporative drying at this exposed moorland site.
Average temperature of only 6.8°C over the past week limits evaporation rates, slowing the drying process considerably compared to summer conditions.
Average humidity of 79% over the past week reduces the vapour pressure deficit, significantly slowing evaporative drying from the rock surface.
1.8mm forecast for April 3 will re-wet surfaces and reset any drying progress, with further rain expected on April 4 and 5.
Recommendations
3
- If visiting today, carefully check the ground at the base of the crag and feel the rock in shaded cracks and lower sections — if either feels damp, do not climb.
- Avoid problems with horizontal breaks, seepage lines, or crack systems as these will hold moisture longest after the prolonged wet March.
- Consider waiting until after the dry spell forecast for April 6 to allow a proper drying window, as the next few days bring further rain.
Climbing Outlook